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41.
42.

Background  

The purpose of this study was to evaluate the long-term results of partial liver resection for benign liver lesions.  相似文献   
43.
Giant cell tumor of bone (GCTB) is a benign bone tumor with a shown clinical behavior of local recurrences and rare distant metastases. GCTB is composed of uniformly distributed osteoclastic giant cells, thought to originate from the fusion of monocyte–macrophage lineage cells, in a background consisting of mononuclear rounded cells and spindle‐shaped cells. Several reports showed the specific expression of markers, such as CD14 on the mononuclear rounded cell population, however, lacking osteoclastic giant cells. Blood monocytes that were CD14+, CD33+, or CD14+/CD33+ have also been shown to be programmed as pre‐osteoclasts. The macrophage marker CD33 is expressed earlier than CD14 in macrophage maturation, whereas CD14 is expressed longer than CD33. The aim of this study was to investigate CD14/CD33 expression profiles in GCTB. Nineteen GCTB tumor samples of 19 patients were studied. Immunofluorescent analyses were performed with monoclonal antibodies against CD14, CD33, RANK, and CD51. To unambiguously further prove the expression of these molecules, quantitative RT‐PCR was used with subsequent sequencing of its products. All samples showed similar immunoreactivity profiles. The mononuclear rounded cell population was positive for RANK, CD51, CD14, and CD33. The osteoclastic giant cell population expressed RANK and CD51, as well as CD33, but was consistently negative for CD14 expression. The CD14 and CD33 profiles were confirmed by quantitative RT‐PCR. These RT‐PCR products were sequence verified. Osteoclasts in GCTB are the result of fusion of CD33‐expressing pre‐osteoclasts that further fuse with CD14+ mononuclear cells. Although these results reflect a static rather than a dynamic spectrum, we strongly believe that osteoclastogenesis seems not to be the exclusive result of fusion of intratumoral CD14+ mononuclear cells. Moreover, CD33‐modulated osteoclastogenesis opens up the possibility for novel therapeutic directions.  相似文献   
44.
Fulminant hepatic failure (FHF) is a rare but often fatal disease in children. Clinical and laboratory predictors of liver regeneration and recovery, however, have not been well established. We hypothesized that hypophosphatemia may indicate recovery of liver synthetic function in children with FHF. We retrospectively reviewed the medical records of children with FHF who were admitted to UCLA and recovered hepatic function either spontaneously or by liver transplantation (LTx). Serum phosphate (Ph) and prothrombin time or international normalized ratio (INR) were compared over the patient's clinical course. Records of 39 children who spontaneously recovered experienced profound hypophosphatemia that resolved as liver synthetic function improved. Similar patterns were seen in the 84 children who recovered after LTx. We found that hypophosphatemia precedes the recovery of liver synthetic function in children with FHF who recovered with or without transplantation, and that Ph levels return to normal as liver synthetic function improves. These data suggest that hypophosphatemia may be a useful laboratory indicator of recovering liver function in children with FHF.  相似文献   
45.
BACKGROUND: Breast cancer tumor ablation as part of a multimodality approach in the treatment of breast cancer is the subject of recent interest. This study was conducted to determine if the ability to perform sentinel node biopsy was impaired after thermal-induced ablation of breast cancer. METHODS: We studied patients who had sentinel node biopsy after preoperative focused microwave phased array for breast cancer ablation. RESULTS: Twenty-one patients with T1-T2 breast cancer and clinically negative axilla underwent wide local excision and sentinel node biopsy guided by blue dye and sulfur colloid. Surgery was done an average of 17 days after microwave ablation. Fifteen of 22 patients (68%) had histologic evidence of tumor necrosis. Sentinel lymph node mapping was successful in 19 of 21 patients (91%). Axillary metastases were detected in 42% of cases. CONCLUSIONS: This study documents successful sentinel lymph node mapping for patients treated with antecedent local tumor ablation using focused microwave phased array ablation.  相似文献   
46.
Thymectomy by partial sternotomy for the treatment of myasthenia gravis   总被引:5,自引:0,他引:5  
BACKGROUND: Myasthenia gravis is an autoimmune disease characterized by weakness and fatigue of voluntary muscles. Surgical treatment of choice for myasthenia gravis has been thymectomy. However, thymectomy indications and surgical approach are still controversial. The purpose of this study is to evaluate the efficacy of partial median sternotomy approach to the thymus. METHODS: From 1973 to 1999, 478 patients with myasthenia gravis underwent thymectomy through a partial median sternotomy. RESULTS: Sixty-one patients (12.7%) had complete remission of symptoms, 299 (62.5%) had a significant improvement, and 83 (17.4%), a mild improvement; whereas 35 patients (7.4%) had no improvement of clinical symptoms. CONCLUSIONS: Partial median sternotomy has shown to be a useful surgical approach to the thymus, as demonstrated by the good functional and aesthetic results, associated with low morbidity and no mortality.  相似文献   
47.
BACKGROUND: Isoniazid (INH) therapy for tuberculosis carries a known risk for hepatoxicity, and leads to hepatic failure in a small subset of patients. This incidence has been described for adults, but is uncertain in children. Our aim was to estimate the incidence of pediatric referrals for INH-related liver failure, and to describe the characteristics and outcomes of these patients. METHODS: The 84 U.S. centers performing pediatric liver transplants between 1987 and 1997 were surveyed regarding patients with INH-induced liver failure. Additional transplant statistics were obtained from the United Network for Organ Sharing. Estimates of the number of children taking preventive INH were derived from a nationwide public health database. RESULTS: Twenty cases of INH-related liver failure were found during a 10-year period. Four patients (20%) recovered spontaneously; 10 (50%) underwent orthotopic liver transplantation (OLT), while six (30%) died awaiting OLT. Mean age at presentation was 9.8 years (range 1.3-17). Mean length of INH therapy was 3.3 months (range 0.5-9). Notably, five patients seen for symptoms of hepatitis were initially told not to stop treatment. INH-associated liver failure accounted for 0.2% (8 of 4679) of all pediatric OLTs, and 14% (8/56) of transplants for drug hepatoxicity. The estimated incidence of liver failure was up to 3.2/100,000 for children on prophylactic INH. CONCLUSIONS: While INH-associated liver failure in children is rare, discontinuation at the onset of symptoms does not assure recovery. This indicates a need for increased awareness of hepatotoxicity risk, expanded biochemical monitoring for children receiving INH, and prompt withdrawal in symptomatic patients.  相似文献   
48.
Sentinel lymph node (SLN) biopsy is increasingly being used as an accurate and less morbid surrogate for axillary dissection. However, a standardized technique in the biopsy of SLNs is not used. Some authors propose subdermal injection to be as accurate as peritumoral intraparenchymal injection (IPI). Our objective is to determine whether the SLNs identified by subdermal injection truly represent SLNs and match those found with IPI. Specific end points of the study were 1) successful localization of the SLN by the IPI of isosulfan blue or the radiocolloid intradermal injection, 2) successful uptake of radiocolloid and isosulfan blue on individual SLN, and 3) determination of the frequency with which the radiocolloid injection detected the "gold standard" blue SLN. SLNs were found in 71 of 73 cases (success rate = 97%). Blue SLNs were identified in 64 patients (88%). SLNs in 61 patients (84%) were radioactive. A total of 112 SLNs were identified in 71 patients (1.6 nodes/patient). Seventy-six of 87 SLNs found with IPI were also radioactive (concordance of 87%). All SLNs harboring metastatic cancer (16 patients) were found by both techniques, being both blue and radioactive. Our results support the concept of shared lymphatic pathways in the breast with a high degree of communication between the subdermal lymphatics and the intraparenchymal lymphatics. The success in identification of the SLN is made simpler and improved by the addition of subdermal radiocolloid injection.  相似文献   
49.
The ability to recognize multicentric breast cancer preoperatively would assist in identifying appropriate candidates for breast conservation surgery. Tc-99m scintimammography (SMM) is an adjunct to conventional mammography in identifying selected patients with breast cancer. The purpose of this study is to report the utility of SMM in identifying patients with multicentric breast cancer. Breast cancer patients treated by mastectomy who underwent a preoperative SMM between 1992 and 1999 were identified using the institution's Tumor Registry. The pathology report of each patient was reviewed for multicentric disease defined as an additional focus of cancer within a different quadrant of the breast or greater than 2.5 cm from the dominant tumor mass. Each patient's preoperative SMM was reviewed and compared with the pathologic findings to obtain correlative data. Fifty-eight women treated by mastectomy had preoperative SMM (age range 35-78 years; median 52 years). Pathology revealed infiltrating ductal carcinoma in 49 patients (84.5%), infiltrating lobular carcinoma in five patients (8.6%), ductal carcinoma in situ in three patients (5.1%), and colloid carcinoma in one patient (1.7%). Multicentric disease was present in the specimens of eight patients for a prevalence of 10.3 per cent. SMM was positive for uptake in 36 of 58 patients (sensitivity 62.1%). The sensitivity, specificity, positive predictive value, and negative predictive value of SMM in the detection of multicentric disease were 62.5, 96, 71, and 94 per cent, respectively. Although the overall sensitivity of SMM in the detection of breast cancer is superior to that of conventional mammography and physical examination in identifying multicentric breast cancer it is not an accurate modality for detecting multicentric disease in this study group. However, it may have limited applications in specific cases.  相似文献   
50.

Background

The relationship between C-reactive protein (CRP), nitric oxide (NO), leptin, adiponectin, and insulin growth factor 1 (IGF-1) is poorly defined in morbidly obese patients before and after gastric bypass and, in some cases, is controversial.

Methods

We examined the plasma of 34 morbidly obese patients before and 1, 6, and 12 months after Roux-en-Y gastric bypass surgery.

Results

Obese people had more CRP (21.3?±?1.8 μg/ml) and leptin (36.9?±?4.0 ng/ml) than those in the control group (nonobese people: CRP?= 6.9?±?0.9 μg/ml, p?<?0.0001; leptin?= 7.5?±?0.4 ng/ml, p?<?0.0001). However, they had less NO (30.4?±?2.7 nmol/ml), IGF-1 (77.5?±?6.6 ng/ml), and adiponectin (11.1?±?1.0 μg/ml) than those in the control group (NO?= 45.8?±?3.9 nmol/ml, p?=?0.0059; IGF-1?= 202.0?±?12.0 ng/ml, p?<?0.0001; adiponectin?= 18.0?±?2.0 μg/ml, p?<?0.0001). During weight loss, the amount of CRP and leptin decreased until they reached the nonobese values, but the level of NO remained lower than in nonobese people, even 1 year after surgery. The linear regression slopes were negative and very significant for leptin (p?=?0.0005) and CRP (p?=?0.0018) but were less significant for NO (p?=?0.0221). IGF-1 displayed a very good linear regression (both negative and significant) with some anthropometric parameters, including body mass index (p?=?0.0025), total fat (p?=?0.0177), and the percentage of fat (p?<?0.0001).

Conclusion

For the first time, we report the relationship between IGF-1 and CRP, NO, leptin, and adiponectin. For all these parameters, the best and most widely demonstrated improvements in comorbidities before and during weight loss in morbid obesity were associated with CRP and leptin.  相似文献   
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